Surah Al-Anfal — Ayah 31 (8:31)
وَإِذَا تُتۡلَىٰ عَلَيۡهِمۡ ءَايَٰتُنَا قَالُواْ قَدۡ سَمِعۡنَا لَوۡ نَشَآءُ لَقُلۡنَا مِثۡلَ هَٰذَآ إِنۡ هَٰذَآ إِلَّآ أَسَٰطِيرُ ٱلۡأَوَّلِينَ ٣١
English translation (Saheeh International)
And when Our verses are recited to them, they say, "We have heard. If we willed, we could say [something] like this. This is not but legends of the former peoples."
Brief commentary
If Allah’s words are recited to them, they say – stubborn against the truth, considering themselves above it, and disbelieving – that they have heard something similar before, and that if they wanted to say something similar to the Qur’ān they could, saying that the Qur’ān is just the fables of earlier peoples.